https://www.espn.com/mlb/story/_/id/39920849/ohtani-interpreter-ippei-mizuhara-stole-16m
Investigators also relied on recorded phone calls from the bank in which Mizuhara falsely identified himself as Ohtani to "trick and deceive" bank employees into authorizing the transfers.

一平が大谷と偽り銀行員を騙して送金を承認させた銀行からの録音電話が発見される